In general, a portable digital device such as a digital camera, a digital camcorder, and a smart phone, may store content (e.g., photos, video, music, etc.) in a storage medium. Optionally, the device stores the content in an embedded storage space. Mostly, however, an external storage medium is used as a small-sized detachable storage medium. The external storage medium may be used to conveniently move/cope the content to another device, and may be replaced with an external storage medium having great capacity to store a great amount of content.
When it is intended to simultaneously use a plurality of external storage media in an electronic device, the plurality of external storage media may be attached to respective holders prepared at different locations of a user device. It may be difficult to make the user device have a small size due to the plurality of holders. Further, a user may feel inconvenience when the plurality of holders are attached to the respective external storage media one-by-one.